Kelly Clarkson, Florida Georgia Line singer Brian Kelley and more have massive, lavish and very high-priced homes on the market that have been sitting unsold, and Nashville's Tennessean newspaper offers a plausible explanation.

Clarkson listed her 20,000 square-foot mansion in the Nashville suburb of Hendersonville for $8.75 million in March of 2017, and the massively luxurious home — which features seven bedrooms, eight full bathrooms and three half bathrooms — remains unsold nearly two years later. That's despite its extraordinary amenities, which include sweeping double staircases, formal living and dining rooms, a wet bar next to the pool table, a private dock, two spas, a saltwater pool and even a home theater.

See Kelly Clarkson's Extravagant Mansion:

Kelley's massive 70-acre rural compound went on the market for $6.2 million in July of 2018, but according to Redfin, the listing is currently closed after not selling. The property is one of the most famous of all of the country stars' homes in Nashville due to its unique treehouse recording studio, which TV's Treehouse Masters added on to the property after the Florida Georgia Line singer bought it.

See Brian Kelley's Incredible Property:

Jason Aldean and his wife, Brittany, listed their 8,900-square-foot mansion and surrounding 120 acres in the affluent Nashville suburb of Columbia, Tenn., for $7.875 million in August of 2018, and so far the castle-like property — which includes six bedrooms and nine bathrooms, a bowling alley, wet bar, wine cellar and more — remains unsold.

See More Pictures of Jason Aldean's Fairytale Mansion:

The mind-boggling mansion that doubled for Rayna Jaymes' house on TV's Nashville went up for sale in August of 2018 for $17,999,999, and it, too, remains unsold, according to Zillow. The massive abode features six bedrooms, eight bathrooms, three half-bathrooms, and adds to up to 20,533 square feet.

Keith Urban and Nicole Kidman faced a challenge selling their upscale farmhouse outside of Nashville, too. They listed the 5,086-square-foot, four bedroom property for $3.45 million in 2016, and sold it for $2.7 million late in 2018 after dropping the price several times.

The Tennessean attributes the difficulty in selling such expensive homes to the simple fact that there aren't that many buyers in that price range at any given time.

"Not many people walk around with millions of dollars in their pockets," says James Spencer, a real-estate agent with Mossy Oak Properties who deals with higher-end listings. "These (listings) do not come along every day. It will be a good day at our house when the property does sell. But a lot of work goes into it."

Spencer uses targeted ads on social media, in magazines and by mail to attract the kind of high-end buyer that might buy a house in the tens of millions of dollars range, and he says it's not unusual for the seller to have to drop the price, agree to split the land into parcels or even throw in the existing furniture as part of the deal, since furnishing such a large house is so time-consuming and expensive.

That doesn't mean expensive homes aren't selling in Nashville — maybe just not quite that expensive. Nashville star Hayden Panettiere put her four-bedroom, five-bathroom, nearly 5,000-square-foot home in Nashville's exclusive Green Hills neighborhood up for sale for $1.65 million in August of 2018, and it sold for full price in October.

See Hayden Panettiere's Now-Sold House:

Jake Owen listed his 4,918 square foot home for $1.5 million in October of 2017. He sold it just days later for $1,310,000, and it went so fast that he ended up having to move into a 400-square-foot tiny house on the property where he is building his new dream house.

See the Mansion Jake Owen Traded for a Tiny House:

Which one of these jaw-dropping celebrity homes would you buy if you had the money? Let us know in the comments below!